The invention relates to an internal combustion engine, in particular for a motor vehicle with at least one piston which is supported in a cylinder so as to be displaceable over a maximal stroke, and with a connecting rod device for adjusting the compression of the internal combustion engine, wherein the connecting rod device has a transverse lever which on one of its ends is connected by a first joint with a connecting rod articulately arranged on the piston and on its other end is connected by a second joint with an actuatable control lever, wherein the control lever is arranged so a to be pivotal about a third joint, and wherein the transverse lever between the first joint and the second joint is connected by a third joint with a crankpin pin of the crankshaft which crankpin is situated spaced apart to a rotation axis of a crankshaft of the internal combustion engine.
Internal combustion engines of the aforementioned type are known form the state of the art, Thus for example the European patent document EP 1 307 642 B1 discloses an internal combustion engine with variable compression ratio, which has a connecting rod device with which it is possible to adjust the compression of the internal combustion engine during operation. for this a transverse lever is provided whose one end is displaceable by means of the control lever in its position, and whose other end is connected with the connecting rod of the piston. The crankshaft which engages on the transverse lever between the connecting rod and the control lever performs the usual movement which leads to a translatory or oscillating displacement of the piston in the cylinder. By actuating the control lever the angular relationships are changed so that the stroke of the piston in the cylinder changes thereby varying the compression or compression occurring in the cylinder. in the patent document nine parameters of the connecting rod device are defined with the goal to obtain the smallest load exerted on the individual members and with this an optimal smooth running. For this purpose different conditions for the distances of the different joints to each other are defined in relation to the crankshaft radius.